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Subject: Sigma 5 Height
Author: KEN SILVERMAN <k2kw@prodigy.net>
Date: 24-Apr-2003 08:44:58
> My conclusion is that if you want a single lobe (on 20m) then a base
height
> of 5m is about right.

At least someone is keeping me honest! Yes, the feedpoint should be up
around 1/4 wavelength to maximize one big lobe. TOTAL height for a half
wave vertical dipole (which is all I really work with these days) should be
no more than 5/8 at the tip. Sorry for the goof.

> Although there is a dip in the radiation pattern between the high-angle
and
> low-angle lobes, I would not go so far as to call it a null as it is
> generally less that 3 dB.

The null should be much bigger than that. Nulls are formed based on
feedpoint height for both vertical and horizontal arrays - the mechanism is
the same.

Kenny K2KW




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This Thread
  Date   Author  
25-Apr-2003 =?iso-8859-1?B?SlRCIFcwWkQgICDUv9Ss?=
25-Apr-2003 Rich Holoch
25-Apr-2003 Tom Ashley
25-Apr-2003 Alan Day
25-Apr-2003 AndrewRoos
24-Apr-2003 Malcolm Ringel
24-Apr-2003 Guy Olinger, K2AV
24-Apr-2003 Pete Smith
24-Apr-2003 Mike
24-Apr-2003 Guy Olinger, K2AV
24-Apr-2003 AndrewRoos
* 24-Apr-2003 KEN SILVERMAN
24-Apr-2003 AndrewRoos
23-Apr-2003 KEN SILVERMAN
23-Apr-2003 Rich Holoch
23-Apr-2003 Rich Holoch
23-Apr-2003 Rich Holoch
This Author (Apr-2003)
  Subject   Date  
* Sigma 5 Height 24-Apr-2003
Sigma 5 Height 23-Apr-2003
Sigma Vs 30-Apr-2003